I have a [KUS SSS][1] Water level sensor for my RV that I would like to have trigger a [NO 12v solenoid valve][2] to turn off when my tank has reached full (and ideally also sound a little piezo). The sensor ranges from 240 Ω empty to 33 Ω full. I'd like to trigger at about 50 Ω. I'm wondering what would be the simple circuit to make this happen?



  [1]: http://www.wemausa.com/sensors/level-FuelWater.shtml#.Xl6jixNKh24
  [2]: https://www.electricsolenoidvalves.com/1-2-12v-dc-electric-plastic-solenoid-valve-normally-open/?gclid=CjwKCAiAnfjyBRBxEiwA-EECLAhHHMXVI_ZEcoDEaIDnQ0uo8jUzUqBAN7lTIjnfzBfGlHnmLFBPkxoCLlEQAvD_BwE